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Show cools it will contract and draw the up per glass on the paper and create at air-tight joint. The upper glass car be taken lip and the. lower will clinf to it. EASY TO CREATE A VACUUM Task Usually Considered a Hard Matter Mat-ter May Be Performed In a Simple Manner. If you have ever worked in a physical physi-cal laboratory you probably have seen a vacuum receiver and learned how difficult it Is to create a perfect vacuum vac-uum even with this instrument. A vacuum can be created in a simple sim-ple way by using two drinking glasses, . -.mall caoJjB end and a piece of. blot ting paper. The glasses must be the same size and of the thin glass kind. The candle end is lighted and' put into' one glass, the blotting paper is well dampened and placed on top of the, glass, tire other glass inverted and. its rim placed exactly over the lower one and pressed down tightly. The candle will burn up all the oxygen in the glass and go out The air in the glass being heated will expand and some of it. will be forced out from under the moist paper; pa-per; then as the portion remaining i |